<template>
  <div id="app">
    <div>
      <span>姓名:</span>
      <input
        type="text"
        v-model.trim="name"
      />
    </div>
    <div>
      <span>年龄:</span>
      <input
        type="number"
        v-model.number="age"
      />
    </div>
    <div>
      <span>性别:</span>
      <select v-model="gender">
        <option value="男">男</option>
        <option value="女">女</option>
      </select>
    </div>
    <div>
      <button @click="btn">添加/修改</button>
    </div>
    <div>
      <table
        border="1"
        cellpadding="10"
        cellspacing="0"
      >
        <tr>
          <th>序号</th>
          <th>姓名</th>
          <th>年龄</th>
          <th>性别</th>
          <th>操作</th>
        </tr>
        <tr
          v-for="(item, index) in arr"
          :key="item.id"
        >
          <td>{{ item.id }}</td>
          <td>{{ item.name }}</td>
          <td>{{ item.age }}</td>
          <td>{{ item.gender }}</td>
          <td>
            <button @click="del(index)">删除</button>
            <button @click="edit(index)">编辑</button>
          </td>
        </tr>
        <tr v-if="arr.length === 0">
          <td colspan="5">暂无数据</td>
        </tr>
      </table>
    </div>
  </div>
</template>
<script>
export default {
  data() {
    return {
      id: 0,
      name: "",
      age: 18,
      gender: "男",
      arr: [
        {
          id: 1,
          name: "Jack",
          age: 18,
          gender: "男",
        },
        {
          id: 2,
          name: "Rose",
          age: 19,
          gender: "女",
        },
      ],
    };
  },
  methods: {
    btn() {
      if (this.name === "" || this.age < 0) {
        return alert("请输入用户名或合法年龄");
      }
      if (this.id === 0) {
        this.arr.push({
          id: this.arr[this.arr.length - 1].id + 1 || 100,
          name: this.name,
          age: this.age,
          gender: this.gender,
        });
      } else {
        // 查找当前 id 在数组中的下标
        const index = this.arr.findIndex((item) => (item.id === this.id));
        this.arr[index].name = this.name;
        this.arr[index].age = this.age;
        this.arr[index].gender = this.gender;
        this.arr[index].id = this.id;
      }
      // 重置数据
      this.name = "";
      this.age = 18;
      this.gender = "男";
      this.id = 0;
    },
    del(index) {
      this.arr.splice(index, 1);
    },
    edit(index) {
      this.id = this.arr[index].id;
      this.name = this.arr[index].name;
      this.age = this.arr[index].age;
      this.gender = this.arr[index].gender;
    },
  },
};
</script>
